Method for developing silver halide photosensitive material

ABSTRACT

It is disclosed that the use of   WHEREIN R1 and R2 are each alkyl groups having 1 to 4 carbon atoms improves the photographic developing characteristics of hydroquinone.

I United States Patent 11 1 1111 3,804,624 Arai et al. Apr. 16, 1974 METHOD FOR DEVELOPING SILVER 3,257,207 6/1966 Green 96/29 HALIDE PHQTOSENSITIVE MATERIAL 3,265,499 8/1966 Wrliems 96/66 3,600,176 8/1971 Haist 96/66 [75] Inventors: Atsuaki Arai; Kinji Ohkubo;

Tatsuya Tajima; Mitsugu Tanaka; OTHER PUBLICAFHONS Yoshllloll su h ya, all Of PSA Journal, Section B, Nov. 1953, Henn, pp. Kanagawa, Japan 149-150. [73] Assignee: Fuji Photo Film Co., Ltd.,

Kanagawa Japan Primary Exammer--J. Travls Brown Assistant Examiner-M. F. Kelley [22] Flled: 09L 1971 Attorney, Agent, or Firm-Surghrue, Rothwell, Mion, 21 App]. No.1 192,951 & Macpeak [30] Foreign Application Priority Data [57] ABSTRACT Oct. 27 1970 Japan 45-94868 is disclosed that the use [52] US. Cl. 96/66 R, 96/66.3, 96/76 R, R1

96/95 H [51] Int. Cl G03c 5/30, 6030 1/06 58 Field of Search 96/66, 66.3, 95 R1 5 References Cited wherein R and R are each alkyl groups having 1 to 4 UNITED STATES PATENTS carbon atoms improves the photographic developing characteristics of hydroquinone. 3,134,673 5/1964 Gangum 96/55 3,l08,001 10/1963 Green 96/29 17 Claims, 1 Drawing Figure DENSITY/D) TIME OF DEVELOPMENT (SEC) FATENTEDAPR 16 1974 TIME OF DEVELOPMENT (SEQ) METHOD FOR DEVELOPING SILVER HALIDE PHOTOSENSITIVE MATERIAL BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for developing silver halide photosensitive material. More par ticularly, it is the improvement of the developing activity of hydroquinone by the use of a specific compound in combination with the hydroquinone.

2. Description of the Prior Art Photosensitive materials have been heretofore prepared by coating a photosensitive silver halide emulsion on a support material such as a glass plate, paper, plastic films, etc., followed by drying the coated product. After the thus prepared photosensitive material has been exposed to light, it is developed in a developer liquid which is an alkaline aqueous solution containing a developing agent as its essential ingredient and thereafter sequentially subjected to stopping, fixation and water-rinsing treatments.

These treatments, however, require long periods of time, so that many improvements for shortening the processing time have been proposed in the art. Examples of these improved methods include high temperature processing, single-bath development and fixation, double bath stabilization treatment, etc.. One of the currently employed methods for shortening the time of development comprises adding a developing agent to a silver halide emulsion layer and then treating the layer in a highly alkaline aqueous solution containing an alkali agent and other photographic additives such as antioxidants and retarders. The advantageous feature of this method resides in making quick development processing possible with shortened developing time which is brought forth by the use of a highly increased pH of a processing liquid that can be allowed only when no developing agent is contained in the processing liquid thereby not causing any degradation in the storability of the processing liquid.

The silver halide photosensitive material to be employed suitably in the above-described method includes silver chloride emulsions and silver chlorobromide emulsions having less silver bromide content, which inherently have a higher rate of developing reaction than is common.

On the other hand, various attempts have been made to apply similar quick processing'even to silver chlorobromide emulsions of a high silver bromide content, pure silver bromide emulsions and silver iodobromide emulsions, by adding a developing agent to these emulsions. However, since each of these silver chlorobromide emulsions, pure silver bromide emulsions and silver iodobromide emulsions have slower developing reaction rates than that of the silver chloride emulsions, it has been possible to obtain satisfactorily desirable photographic characteristics by this treatment within short periods of time.

It is also well known in the art that excellent photographic characteristics (never attainable with the use of hydroquinone alone) csn be obtained in the usual development process for silver halide photosensitive emulsions containing no added developing agents by using a developing liquid containing hydroquinone simultaneously in combination with a developing agent having super additive powers such as l-phenyl-3- pyrazolidone or N-methyl-p-aminophenol (commonly known as P0 or MQ developers). In addition, it is disclosed in U.S. Pat. No. 2,751,297 that the rate of development is accelerated by the addition of l-phenyl-3- pyrazolidone to a single hydroquinone solution or to a MQ developer.

By utilizing these prior teachings, we have made an attempt to accelerate development when using silver chlorobromide emulsions, silver bromide emulsions and silver iodobromide emulsions, each containing a developing agent admixed therein. It was found, however, that the addition of these accelerators, i.e., l-phenyl-3-pyrazolidone, N-methyl-p-aminopheno] etc. to these emulsions was unsuccessful, because these accelerator compounds are very susceptible to oxidation which in turn not only causes a degradation of the activity of these compounds during the storage of the articles but also invites discoloration Ior fouling of the sup port base.

It has been also reported that certain p-aminophenol derivatives such as compound (I) shown below, which is disclosed in Japanese Pat. publication No. 37-5993, and compound (II) shown below, which is disclosed in U.S. Pat. No. 3,265,499, have more excellent super additive powers than the above-mentioned lphenyl-3- pyrazolidone and N-methyl-p-aminophenol when they are used in combination with hydroquinone.

We have also made an attempt so as to improve the above drawbacks encountered in the use of the compound set forth in the above-mentioned U.S. patent, by adding such compounds to the emulsions described heretofore. However, unsuccessful results have been obtained in that the photographic emulsions incorporated with such compounds have a tendency to fog, and the prevention of this fogging by resorting to the addition of known fog inhibitors caused an appreciable decrease in the developing speed. Compounds I and II referred to above are below:

wherein R is typically an alkyl group having 1 to 6 car bon atoms, R is typically a methyl or ethyl group and X is typically a methyl, ethyl, or an alkoxyl group having 1 to 6 carbon atoms; and

XI CHz-CH:

wherein each of X and X is typically a hydrogen atom,

a halogen atom, an alkyl group, an alkoxyl group, an alkylamido group, etc..

OBJECTS OF THE INVENTION A primary object of this invention is to improve the photographic characteristics in a conventional rapid developing process of photographic paper, by adding a compound of the general formula (III) shown below into a silver halide emulsion layer and/or adjacent layer such as a protective layer or undercoating layer containing a developing agent admixed therein.

Formula [II is as follows:

(III) and 4. 4-di-n-butylamino-2-phenyl phenol hydrochloride.

These compounds are employed with hydroquinone in the process, material and/or alkaline solution of the present invention as follows:

wherein each of R and R is an alkyl group containing 1 to 4 carbon atoms.

A further object of this invention is to employ a compound of the general formula (III) as an essential developing agent having exceptional additivity when combined with hydroquinone for developing monochromic and color photographs.

A still further object of this invention is to accelerate the developing speed of the usual developing treatment by adding the compound of the general formula (III) into the emulsion layer, a protective layer and/or the undercoating layer of silver halide photosensitive materials containing no developing agent added therein.

BRIEF SUMMARY OF THE INVENTION We have now found that the aforementioned disadvantages can be overcome by the addition to a silver halide photographic emulsion of a compound represented by the general formula (III) in combination with hydroquinone and that excellent photographic characteristics can be obtained by developing this photographic material with a single hydroquinone developer. We have also discovered that an alkaline developing liquid containing the compound represented by the general formula (Ill) together with hydroquinone is an excellent photographic developing liquid.

wherein each of R and R is an alkyl group containing 1 to 4 carbon atoms.

DETAILED DESCRIPTION OF THE INVENTION The novel developing agent of the above general formula (Ill) may be usually used in the form of stable salts such as the hydrochloride or sulfate salts rather than in the form of the free amine. More particularly, the compounds of formula (III) identified below have proved to be very suitable for being applied in the process of the present invention:

1. 4-diethylamino-2-phenyl phenol hydrochloride;

2. 4-(N-ethyl-N-n-propylamino)-2-phenyl phenol sulfate;

3. 4-dimethylamino-2-phenyl phenol hydrochloride;

The effect of the addition of the compound of the general formula (III) is exerted against each of pure silver chloride, silver chlorobormide, pure silver bromide and silver iodobromide emulsions, and an outstanding effect is obtained when it is used in combination with silver chlorobromide, pure silver bromide or silver iodobromide emulsions, each of which is known to have a slow developing speed.

The developing agent to be used in combination with the compound of the general formula (III) in accordance with the present invention is not limited to any specific type, and it is possible to use any compounds which are conventionally employed as photographic developing agents having reducing reactivity. Such developing agents typically include hydroquinone or its derivatives, catecohol or its derivatives, ascorbic acid, etc..

The support material to be used for supporting the silver halide photosensitive material may be any one of those capable of supporting silver halide emulsions and is typically exemplified by paper and plastic film which may be further provided with baryta layer(s) or undercoating layer(s).

The silver halide emulsion to be used is intended to include silver halide photosensitive materials, and may contain gelatin or other synthetic resins such as polyvinyl alcohol, polyvinyl acetal, etc..

Since the compound represented by the general formula (III) is a novel compound, the method for its preparation will be explained hereinafter in detail.

SYNTHETIC EXAMPLE 1 4-Diethylamino-Z-phenyl-phenol Hydrochloride In accordance with a conventional method (e.g., Jikken Kagaku Koza, 17, (A), pp. 509) ohydroxybiphenyl was coupled with a diazonium salt of sulfanylic acid to give an azo dye which was subsequently reduced with sodium hydrosulfite into 4-amino-2-phenyl-phenol.

A mixture of 15 g of the thus prepared 4-amino-2- phenyl-phenol, 25.2g of ethyl iodide, 11.1g of anhydrous potassium carbonate and 450 ml. of ethanol was heated under refluxing conditions for 12 hours with stirring. After being cooled to room temperature, the reaction product mixture was filtered under suction and the residual solid mass recovered on filter paper was washed twice with ethanol. After combining the resulting filtrate with the wash liquid, the liquid was distilled under reduced pressure to remove ethanol in an oil bath and the residue was impregnated with hot ether twice. After removing the ether therefrom, the residue was distilled under reduced pressure of 1 mm Hg while raising the temperature of the oil bath to 200C. and collecting the fraction which was distilled out. The fraction thus recovered wasdissolved in about 500 ml. of ether and dry hydrogen gas was passed therethrough to give 9.7g (yield of 43.1 percent) of white crystalline powder of the desired compound. Recrystallization of this compound from dilute aqueous hydrochloric acid produced sublimative colorless flaky crystals.

SYNTHETIC EXAMPLE 2 4-Di-n-propylamino-2-phenyl-phenol Hydrochloride In a manner similar to the above Synthetic Example 1, there was obtained 10.5g (yield of 42.9 percent) of the white powdery crystals of the desired product using 15 g of 4-amino-2-phenyl-phenol, 27.3g of n-propyl iodide, 1 1.1 g of anhydrous potassium carbonate and 450 ml. of ethanol.

The present invention will be further explained in more detail by the following examples.

EXAMPLE 1 Photographic baryta paper of 150 g/cm was coated with a solution containing 400 cc of a silver halide gelatin emulsion comprising 50g gelatin and g silver chlorobromide having a silver bromide content of 60 mol percent, a necessary hardening agent, a coating additive and the developing agents shown in Table 1. The coated papers were each further coated, under the set state before drying, with a protective layer consisting of 20g gelatin, 6 cc saponin (as 6 percent methanol solution) and one liter of water and thereafter dried to prepare each sample of A to G as shown in Table 1. Each sample was then exposed to light through an optical wedge (step wedge) and developed with an activated solution having the following composition:

Composition of Activated Solution:

Anhydrous sodium sulfite 45 g Potassium hydroxide 48 g Potassium bromide 1.3 Water to make the entire solution to 1,000 cc.

From this Table 1, it will be noted that the sample G to which the compound of this invention was added exhibits remarkably high values in sensitivity, maximum density and gamma, and has excellent qualities.

EXAMPLE 2 A coating solution was prepared by adding a necessary hardening agent and a coating additive to 400 cc 0 ofa silver halide gelating emulsion containing g gelatin and 20 silver iodobromide in which silver iodide occupied 1.5 mol percent. This coating solution was applied to a photographic baryta paper of 150 g/m. This coated paper was further coated, under the set state, with a coating solution comprising 20g of gelatin, a mixture of 30g of hydroquinone and 1.5g of 4-diethy1amino-2-phenylphenol hydrochloride as an essential developing ingredient, 2g of sodium benzene sulfinate as an antioxidant for the developing agent, 3 cc of 30 percent aqueous formalin solution, 6 cc of 6 percent methanol solution of saponin and one liter of water and thereafter dried.

A comparative sample was similarly prepared but adding no 4-diethy1amino-2-phen1y1phenol hydrochloride.

Thus prepared samples were treated according to the manner similar to Example 1. The sample of this invention exhibits superior values in sensitivity, maximum density and in gamma to the control sample.

EXAMPLE 3 Photographic baryta paper of 150 g/m was coated with a solution comprising 50g of gelatin, 35g of hydroquinone, 1.8g of 4-dimethylamino-2-phenylphenol hydrochloride, 2g of sodium benzene sulfinate as an antioxidant for hydroquinone, 2 cc of 30 percent aqueous formalin solution, 1.0g of a fluorescent whitening agent, Blankopher BUP" (manufactured by Bayer Co., West Germany) and one liter of water. A coating solution comprising 400 cc of silver halide gelatin emulsion containing 20g of silver chlorobromide in which the content of silver bromide was mol percent, and other necessary additives such as a hardening agent and a coating additive were coated thereon. The coated paper was further provided while under the set state, with a protective layer by coating thereon a solution comprising 20g of gelatin, 6 cc of 6 percent methanol, a solution of saponin and one liter of water.

4-diethylamino-2-pheny1- phenol A comparison sample was prepared similarly but no 4-dimethyl-amino-2-phenylphenol hydrochloride was added.

Both samples (photographic paper) thus prepared were subjected to a similar treatment as described in Example 1. It was noted that the sample according to this invention, i.e., 4-dimethylamino-Z-phenylphenol being added to the undercoating layer thereof gave excellent results in extremely higher values of sensitivity, maximum density and in gamma than those obtained with the control sample.

EXAMPLE 4 A coating solution was prepared by adding a necessary hardening agent and a coating additive to 400 cc of a silver halide gelatin emulsion containing 50g of gelatin and g of silver chlorobromide with a silver bromide content of 50 mol percent. The coating solution was applied to photographic baryta paper of 150 g/cm to thereby prepare a photographic paper. This apper was developed with the use of the developing liquid having the following composition, and the change in density in relation to the developing period at a constant exposure dosage is illustrated in FIG. 1.

Curve A Hydroquinone alone was used Curve B Hydroquinone is used in combination with 1-phenyl-3-pyrazolidone Curve C Hydroquinone used in combination with metal Curve D Hydroquinone used in combination with 4-diethylamino-Z-methyl-phenol-hydrochloride Curve E Hydroquinone used in combination with 4-diethylamino-phenylphenol Composition of the Developing Bath (pH 10.9)

Anhydrous sodium sulfite 20 Hydroquinone 3 Anhydrous sodium carbonate 15 Potassium bromide 1 Cooperative developing agent shown in the table above (at the molar ratio of 1/20 to hydroquinone) Water to make the entire solution to 1,000 cc.

Photographic baryta paper of 150 g/m was coated with a coating solution prepared by adding 30 g hydroquinone and other necessary additives to every one Kg of a silver halide emulsion containing 40 g of silver chlorobromide (60 mol percent silver bromide) per 125 g of gelatin and then dried. The thus prepared photographic paper was exposed to light through a step wedge, then developed for 4 seconds with the activated solution used in Example 1 and thereafter stabilized with a stabilizer solution containing ammonium thiocyanate. For the purpose of comparison, the same treatment was repeated but using as the activated solution a solution containing 0.9 g per liter added compound of Synthetic Example 1. The results obtained after measuring specific sensitivity, maximum density and gamma are given in Table 2.

As can be understood from Table 2, the compound of the Synthetic Example (1 proves to greatly accelerate the developing activity of hydroquinone.

EXAMPLE 6 Photographic baryta paper of g/m was coated with an emulsion containing 2.2g of the compound of Synthetic Example (1 per one Kg. of the silver halide emulsion of Example 5 and other additives, then dried to give a photographic paper. This photographic paper and another photographic paper prepared by using an emulsion containing the compound of Synthetic Example (1) were each exposed to light through a step wedge, then developed for 4 seconds with an activated solution containing 20g of hydroquinone per liter of the solution shown in Example 1, and thereafter stabilized with a stabilizer solution containing ammonium rhodanate. The results obtained by measuring the specific sensitivity, maximum density and gamma are given in Table 3.

It can be clearly understood from the above result that the compound of Synthetic Example (1) greatly accelerates the development by hydroquinone.

As having been set forth in greater detail, it will be understood that the present invention is not only adaptable for a silver halide photosensitive material containing a developing agent in the emulsion layer thereof, but also quite similarly applicable with excellent results to conventionally used silver halide photosensitive materials for photographic or copying purposes containing no developing agent in the emulsion layer thereof.

What is claimed is:

1. A photographic developing process which comprises developing an exposed light-sensitive silver halide emulsion layer of a multilayer photographic element with an alkaline solution hydroquinone and a derivative of p-aminophenol having the general formula:

wherein each of R and R is an alkyl group having 1 to 4 carbon atoms.

2. A photographic developing process according to claim 1, wherein said hydroquinone is incorporated in said layer, in an adjacent layer to said emulsion layer or in said layer and in an adjacent layer to said emulsion layer, and said derivative is incorporated in said alkaline solution.

3. A photographic developing process according to claim 1, wherein said hydroquinone is incorporated in said alkaline solution, and said derivative is incorporated in said layer, in an adjacent layer to said emulsion layer or in said layer and in an adjacent layer to said emulsion layer.

4. A photographic developing process according to claim 1, wherein said hydroquinone and said derivative are incorporated in said layer, in an adjacent layer to said emulsion layer or in said layer and in an adjacent layer to said emulsion layer.

5. A photographic developing process according to claim 1, wherein said hydroquinone and said derivative are incorporated in said alkaline solution.

6. A photographic developing process according to claim 2, wherein the amount of said hydroquinone is from 5 to 500 grams per mole of light-sensitive silver halide.

7. A photographic developing process according to claim 4, wherein the amount of said hydroquinone is from 5 to 500 grams per mole of light-sensitive silver halide.

8. A photographic developing process according to claim 3, wherein the amount of said derivative is from 0.05 to 50 grams per mole of light-sensitive silver halide.

9. A photographic developing process according to claim 4, wherein the amount of said derivative is from 0.05 to 50 grams per mole of light-sensitive silver halide.

10. A photographic developing process according to claim 3, wherein the amount of said hydroquinone is from 1 to 70 grams per liter of said alkaline solution.

11. A photographic developing process according to claim 5, wherein the amount of said hydroquinone is from I to 70 grams per liter of said alkaline solution.

material containing a derivative of p-amino-phenol having the general formula:

wherein each of said R and R is an alkyl group having 1 to 4 carbon atoms said derivative showing a superadditive effect in combination with hydroquinone when said photographic material is developed in said derivative and hydroquinone.

16. An alkaline solution for photographic development, which contains a derivative of p-aminophenol having the general formula:

wherein each of R and R is an alkyl group having 1 to 4 carbon atoms, said derivative showing a superadditive effect in combination with hydroquinone dur ing photographic development.

17. The photographic developing process according to claim 1, wherein said hydroquinone is incorporated in said alkaline solution and said derivative is incorporated in any one of said emulsion layer, a protective layer adjacent to said emulsion layer, or an undercoat layer adjacent to said emulsion layer. 

2. A photographic developing process according to claim 1, wherein said hydroquinone is incorporated in said layer, in an adjacent layer to said emulsion layer or in said layer and in an adjacent layer to said emulsion layer, and said derivative is incorporated in said alkaline solution.
 3. A photographic developing process according to claim 1, wherein said hydroquinone is incorporated in said alkaline solution, and said derivative is incorporated in said layer, in an adjacent layer to said emulsion layer or in said layer and in an adjacent layer to said emulsion layer.
 4. A photographic developing process according to claim 1, wherein said hydroquinone and said derivative are incorporated in said layer, in an adjacent layer to said emulsion layer or in said layer and in an adjacent layer to said emulsion layer.
 5. A photographic developing process according to claim 1, wherein said hydroquinone and said derivative are incorporated in said alkaline solution.
 6. A photographic developing process according to claim 2, wherein the amount of said hydroquinone is from 5 to 500 grams per mole of light-sensitive silver halide.
 7. A photographic developing process according to claim 4, wherein the amount of said hydroquinone is from 5 to 500 grams per mole of light-sensitive silver halide.
 8. A photographic developing process according to claim 3, wherein the amount of said derivative is from 0.05 to 50 grams per mole of light-sensitive silver halide.
 9. A photographic developing process according to claim 4, wherein the amount of said derivative is from 0.05 to 50 grams per mole of light-sensitive silver halide.
 10. A photographic developing process according to claim 3, wherein the amount of said hydroquinone is from 1 to 70 grams per liter of said alkaline solution.
 11. A photographic developing process according to claim 5, wherein the amount of said hydroquinone is from 1 to 70 grams per liter of said alkaline solution.
 12. A photographic developing process according to claim 2, wherein the amount of said derivative is from 0.01 to 20 grams per liter of said alkaline solution.
 13. A photographic developing process according to claim 5, wherein the amount of said derivative is from 0.01 to 20 grams per liter of said alkaline solution.
 14. A photographic developing process according to claim 1, wherein said derivative is selected from the group consisting of 4-diethylamino-2-phenyl phenol hydrochloride and 4-n-dibutylamino-2-phenyl phenol hydrochloride.
 15. A photographic material having at least one light sensitive silver halide emulsion layer, said photographic material containing a derivative of p-amino-phenol having the general formula:
 16. An alkaline solution for photographic development, which contains a derivative of p-aminophenol having the general formula:
 17. The photographic developing process according to claim 1, wherein said hydroquinone is incorporated in said alkaline solution and said derivative is incorporated in any one of said emulsion layer, a protective layer adjacent to said emulsion layer, or an undercoat layer adjacent to said emulsion layer. 